The agency says Hassan Rouhani told Pakistani Prime Minister Muhammad Nawaz Sharif in a phone call that, following the establishment of a joint commission, “we expected serious actions by the Pakistani authorities to free the hostages.”

Five guards were kidnapped by the Jaish al-Adl militant group last month outside Sarbaz, a town near Iran’s border with Pakistan. A local official said two days ago that one was killed.

Iran’s semi-official Fars news agency meanwhile reported that the country’s foreign minister, Mohammad Javad Zarif, sent a letter to Secretary-General Ban Ki-moon denouncing the abduction as the latest of a series of “terrorist acts” against Iran, including bomb and other attacks on Iranian diplomatic interests in Lebanon, Yemen, and Pakistan.

Zarif said “all available evidence” pointed to “state-sponsored extremist groups.” Some of the attacks, however, have been claimed by Sunni radical groups. They consider the Islamic Republic an enemy and are particularly incensed by its support of Syria, whose government is stacked with members of a Shiite offshoot sect.